In this video, I'm going to try something I don't believe anyone has ever made a video of before.
I have this very special microphone that is able to record frequencies
five times wider than what a normal microphone can do. Five times higher frequencies. That means that
it is going to go way into the ultrasonic range, even beyond what cats and dogs can normally hear.
So then I'm going to actually use this to record certain things that produce
ultrasonic sounds. Then I can squash those sounds down into the audible human range
so we can actually hear what they sound like on a relative basis, at least like
never before. And I've got several different things here, so it should be pretty cool.
But to be clear, this is not a review of any of these devices. It's literally just focusing on the
ultrasonic sound aspect of them. I've no idea if these actually work for their intended purpose. So
first a quick explanation on how this microphone and everything is going to work. Basically when
you go to record audio, depending on the program you're using, you can have a spectrum view of the
recording. And with this, instead of seeing just a waveform of the loudness of different parts, you
can actually see the loudness based on the actual specific frequency in that part of the audio.
So it's kind of like a heat map. So it's time in one dimension, frequency in another,
and then the color determines the loudness. Now a normal microphone is going to top
out at maximum of like around 20 kHz, this range here. And that's because human hearing
typically tops out absolute maximum at around 20 kHz.
And actually most adults will top out between 15 and 17 kHz depending on age, but it could
be even lower. However, this microphone here is very different. This is the Sanken
CO-100K and like the name suggests it can go up to 100 kHz. Now, considering I just said that
humans can only hear up to 20 kHz or so max, you might be wondering why this would even be useful.
So let me give a demonstration. Say you're making a scary horror movie or something,
and you need monster sounds. So you want to make monster sounds with a normal voice and then
pitch it down to make it sound all scary. So that's what I'm doing for this demonstration.
I'm using the Shure SM7B a very popular podcasting microphone, as well as the Sanken CO-100K. And
then I recorded them simultaneously and I'm going to pitch it down about 60%.
So it sounds very low and monster-like. So now I'll
just play them back to back and you can tell me if you can tell the difference.
So yeah, big difference. As you probably heard the 20 kHz microphone, when you squash it down, it
sounds almost like it's underwater because there's no higher tones. But when you take the 100 kHz,
squash it down, you still kind of have that full 20 kHz range, even though it's squashed so down.
So it actually sounds more realistic. So that's one example of where this might be useful. Another
one is if you're making sound effects by recording various things like, I don't know, snapping a
twig, you want to make it sound more dramatic, then having that extra range to squash and move
around the pitch can be very helpful. And to give a bit of perspective for how other animals hear,
a cat apparently can hear up to around 79 kHz. Whereas a dog can hear up to
maybe around 45 kHz though. Though this is going to vary by the breed of the animal,
as well as the individual frequency, some are more sensitive than others. So anyway,
with this microphone, we can easily hear into the range that normally only animals can.
Now interestingly, when I was looking around for things around the house that
would produce ultrasonic sounds, there aren't really that many. However, there are several
products and devices that are specifically designed to produce ultrasonic sounds,
which is what I focused on here. Now, one quick last point I want to make before we get into that,
is to be clear that when you record the microphone with 100 kHz frequency or whatever,
if you were to play it back on a speaker that could even do that,
you still wouldn't be able to hear it, even though you recorded it. Because it's still above
that frequency range. So we still have to process it and pitch it down to be able
to hear those frequencies. And because of that, it's not like we can ever truly hear
what these things would sound like to a dog or a cat with that natural hearing range.
It's just going to be more of a relative basis, but it still gives,
I think, a good idea. You can still imagine what it would sound like. For example, you can still
imagine whether this would sound annoying or not. So you'll see what I mean. So let
me quickly go through the devices that I have and we're going to be testing.
So first of all, we have two different dog whistles. So
these are going to produce probably slightly different sounds. I also have two different
anti-barking devices for dogs. So these produce different frequencies in the
inaudible range to humans, but dogs can hear it. And supposedly they make a dog stop barking.
And then finally I have these two different ultrasonic rodent repellent devices. So apparently
these produce frequencies that rodents, or I think maybe even bugs or something it claims,
and it's supposed to scare them away or keep them away
within that range. Though a quick warning to anyone with headphones on or loud speakers,
be ready to change the volume knob because some of these are a bit obnoxious sounds.
Okay. So let's start off with the metal dog whistle,
and I'll just play it as recorded. No manipulation.
So it's mostly just a hissing sound, but you can sort of slightly hear
a whistle sound on the high end. And now I'll play it back with a 80% pitch reduction.
So still nothing too crazy, more it just kind of sounds like blowing through a straw.
It's pretty uniform I think, which kind of makes sense if this is advertised as a dog
training whistle. It's not really meant to annoy them, just kind of
make them more easily hear it. And I guess that makes sense. Next we can try the red dog whistle.
So I'll play that here normally.
So this one is definitely more in the human audible range.
It sounds more like a regular whistle. And then here is this one also reduced by 80%.
This one definitely has more of a focused tone, I would say, a more distinct tone.
But other than that, it's not all too different from the previous whistle.
Okay next up I have these two electronic dog whistle type devices. And these are
actually kind of interesting. Though, based on the recordings that I made.
I do believe these have the same, if not a very similar,
sound module. So they produce pretty much the same exact tone.
So I'm just going to talk about them together. When you go to use it, it effectively has no
audible sound to a human. So there's no point in playing it back, you're not going to hear
anything. But when recording it, you can see that it produces a really wacky looking spectrum.
However, I don't believe these lines are actually real. They're
probably what are called harmonics and also a result of what is called aliasing,
which for some reason, seems to occur when the audio is clipping, too loud. So basically
that's when this thing is too close to the microphone. When I backed up across the room,
all these wacky looking lines disappeared, and I was left with just a very solid line on the 25 kHz
there is another thinner line at 50 kHz, but considering that is even outside the range
of dog hearing, I believe that is another harmonic artifact. So I believe basically,
these both just produce a single frequency at 25 kHz and that's it. Oh,
and you audio experts out there? Yes, I am recording of 192 kHz,
the maximum my audio interface does support. So I am getting that frequency range in there. Okay,
so now we can see what frequency this thing is producing, and now we can pitch it down
80%. So get ready to maybe turn down the headphones a little bit. This is annoying.
So, as you can hear, it sounds more of like a flat, single tone. However,
it does not sound exactly like a regular sine wave, a smooth sine wave. This sounds a little
bit more annoying than that. So it probably would be annoying for animals hearing it as
well. And I think that probably makes sense, considering this is meant to like stop barking.
It probably is supposed to sound slightly annoying. And also I'll point out when I
pitched it down, these other random bands appear, and I believe these are also not
truly there. They're just result of recording artifacts. All right so next we can talk about
the two different rodent repellent devices, and I'm not going to name any brand names.
Cause again, these aren't review. And also these seem to be kind of generic
devices that are produced under multiple brand names, so it doesn't really matter
anyway. So the first we have this blue one and this one actually is pretty interesting.
It isn't really what I was expecting. Now like the electronic dog whistle things,
I could not hear this at all naturally, but when I was recording it, the waveform was
very interesting to see developing. You can see it is not just a single tone, but it actually
rises in tone from around 25 kHz to 65 or 70 kHz, I'd say, it kind of varies a little
bit. But that is pretty much consistent with the back of the device that says 25 to 74 kHz range.
So then I lowered it by 85% to get a better idea of what this actually sounds like to
rodents, and I'll let you hear that right now.
So basically it seems like every 400 milliseconds or so, it increases the tone frequency by around
100 Hz and then goes up to 65-75 kHz, then stops for about 10 seconds, and then starts right over
from 25 up again. So that's definitely kind of interesting. Although one thing I noticed is,
a lot of these anti rodent devices say that they're pet safe and that pets won't be annoyed
by it, but I don't see how that is possible because they're in the hearing range of pets.
So if you're going to be using these, I would kind of observe if you have a cat or dog,
if they seem to be avoiding the thing or annoyed by it, then they probably are.
And you might want to reconsider it. Alright and finally we have this other one it's also plugin,
and this one was definitely disappointing. It doesn't seem to really fully work.
It's supposed to have three different settings for what it calls a slight,
middle, or heavy infestation. So good idea in theory, and the frequency range it states
is 22 to 50 kHz. So those are definitely outside the human hearing range, you shouldn't be able
to hear. However, when I went to test both of the lower two settings, I didn't see anything.
It doesn't seem to produce any sounds at all. And I thought okay, maybe it's intermittent,
maybe like the previous one. So I gave it like a good five minute,
and it produced nothing that I saw at all. So I don't know if my unit is just effective, but
it's not exactly encouraging. And you wouldn't exactly know if it's even working or not,
if you bought this normally. Now on the red setting, I immediately was able to tell that it
was doing something, but that's because I could actually hear it. Which obviously I don't think
is supposed to happen. And yes, it was very annoying. And here's what that sounds like.
As you can hear and see, the sound oscillates from 30 kHz dipping way down to around 12 kHz, which
most people will be able to hear that. And it's also way outside the stated range of the device,
which says it bottoms out at 22 kHz, but it goes down to like 12. And I also want to
quickly point out, I believe it's just producing one waveform and the other ones here are just
harmonics again, they're not actually there. Now with that recording, most likely you heard it go
up and then kind of stop and then come back down again. But if we lower it by 85%, we can actually
hear that it is one continuous oscillation. So let me play that back pitched down.
So I think that's kind of interesting before you couldn't hear it into the top ranges,
but then when you bring it down, you can actually hear the whole thing. So because it's changing and
if it's at least as annoying as we think it is, a rodent probably would be deterred by this thing,
if it was actually in the range that it stated, which it's not, it goes into the human hearing
range. Which in my opinion, just makes it completely useless to have around the house.
I would not want this thing around. And I don't believe this is just a defective unit fully
because reading some reviews, they did state that they could hear it in the red mode as well. So
I don't know, I would not recommend this device if you see it, obviously. Still though,
I was definitely very interested while doing all these tests and hopefully you were too.
So let me know what you think down in the comments. And if you know of any particularly
unique ultrasonic sounds that you might think might be worth making additional videos about,
then let me know down there, I'll consider it. And if you're thinking about subscribing, also
be sure to click the bell next to the subscribe button and make videos about once or twice a week.
You don't want those getting lost in the rest of your subscriptions. Now,
if you guys want to keep watching, if you kind of like these sort-of scientific test type things,
the next video I'd recommend is one where I was doing a review of a water cooled mattress
that I got recently. Well, last year. And I did a whole thermal imaging test of it.
I think it was pretty cool. So I'll put that link right there.
So thanks so much for watching guys. And I'll see you in the next video.